The main goal of this Collaborative Proposal is to investigate biochemical, functional, and structural neuroimaging changes following non-invasive brain stimulation in patients with chronic widespread pain: fibromyalgia (FM). The fact that multiple therapeutic modalities which focus on central mechanisms provide modest relief for these patients raises the possibility that the cause for the chronicity of this debilitating disorder may lie within the brain itself. We propose that changes in the cortical milieu may result from prolonged experience of pain and suffering. Our previous results suggest changes in excitatory neurotransmitter levels, connectivity between multiple brain networks, and cortical thickness coincide within central neural loci related to pain perception and modulation in FM. Interestingly, modulation of cortical activity can be achieved noninvasively by a novel tool, transcranial direct current stimulation (tDCS), which has been reported to produce lasting therapeutic effects in chronic pain, especially FM. We propose to study the long-term effects of tDCS application on multiple levels of the central nervous system in FM patients. This project has significant clinical relevance and has the support of collaborators from University of Michigan and Harvard University